Scanning device



June 24, 1930. AMBE T 1,767,718

SCANNING DEVICE Filed Feb. 23, 1929 I 2 Sheets-Sheet l llllllllllll l I I II I June 24, 1930. E. A. TAMBERT SCANNING DEVICE Filed Feb 23, 1929 2 Sheets-Sheet 2 Qwvewmm. Elmer. A. 7272225671.

Patented June 24, 1930 UNITED STATES PATENT OFFICE ELMER A. TAMBER'I, OF CULVEE CITY, CALHORNIA.

SCANNING DEVICE Application filed February 23, 1929. Serial No; 342,011.

This invention relates to the art of trans of a screw. A spot of li ht thrown upon mitting pictures to a distance by electricity. the film as it is moved t en traverses the While the invention is in principle equally entire film area in a long spiral and, passing applicable to the transmission of moving through the film cylinder, afi ects a photo pictures or views having objects in motion electric cell mounted therewithin in accord- (television), the present physical illustraance with the densities of the successive eletive embodiment of the invention is more mental film areas passed before the light particularly adapted to the transmission of spot. The photo electric cell thereupon genstill pictures (telephotography), and the incrates electrical pulsations representing the 1 vention will therefore be specifically dedensity characteristics. of the view, and these scribed and illustrated with that application pulsations are suitably amplified and transparticularly inview, but without necessary mitted to the receiving end of the system, limitation thereto. At the receiving end a raw film is mounted As is well understood in the art, a system similarly to the original transparency and is 15 for the transmission of either still or moving rotated in exact synchronism therewith, but views must comprise some means for changthe spot of light thrown upon its surface in ing the space variations in brightness from thls case is caused to be varied in accordance pomt to point in the view into time variawith the transmitted electrical pulsations, so tions in an electrical current at the sending that successive elemental film areas are light- 20 end of the system, and some means for afi'ectecl in exact accordance with the density changing these time variations in current of the corresponding elemental film area of back into space variations in brightness upon the sending transparency.

a screen or film at the receiving end system. This rotating film-cylinder arrangement The first of these means may comprise is of course not adapted to the requirements 25 some mechanically moved arrangement or of television. In television, the well known device by which'the same efi'ect is obtained rotating scanning disk having a series of as if the view to be transmitted were cut up spirally arranged holes is now ordinarily into a single long strip and passed before a emplo ed. This disk is either arranged to light'sensitive element to produce an electriscan t e sub ect by means of its spirally ar- 30 cal current varying with the brightness ranged holes, the light from an elemental along the strip. The second ofthese means, area of the subject passing through a single which is located at the receiving end of the aperture at any instant to affect the photo system, may comprise a device mechanically electric cell; or, in another arrangement, a driven in exact synchronism with the first spot of light projected froma sin le source 35 .mentioned means, and operating to give the is moved over the entire area of the subject same effect as if the raw film or screen upon by passing through the successive apertures which the picture is to be reproduced were passing before the source, the light reflected cut up into a single long strip and passed from the sub ect in this case afi'ecting photo before the spot of a light beam which is electric cells positioned nearby. By either 40 governed, in intensity by the transmitted of these latter arrangements it is possible to electrical current. transmit either from the moving subject it According to a well known still picture self or fr om a moving picture thereof. And

transmitting system, the means for convert. a televis on dlsk of this type is, of course,

ing space variations in brightness into time also available for the transmission of still variations 'inelectrical current comprises. an pictures, although is far inferiorfor that arrangement whereby a celluloid film transpurpose as regards preservation of detail to parency of the-view is bent into the form of the system plreviously described.

a cylinder and placed in a carriage, which Both of t ese systems, however, have oerrotates the film cylinder in its axis, and tam l mitat1ons. The first described sysmoves it longitudinally on i ts axis by means tem-that in which the trttingis done from a transparenc of the view bent into the form of a cylin er--is obviously limited to the transmission of still pictures converted into the "form of film transparencies, and does not provide for directly transmittn from a. photograph or from the object itsel The second 8 stemthat employed in television-sirloin es a disk that has one aperture for each arallel slice that the picture pictures,

or view is to divded into in transmission, and these apertures must be spaced apart about the disk so that only one aperture is effective at a time. For the present purposes of television, a scanning disk of approximately twenty-four inches in diameter and having fifty apertures has been employed, thus causing the view to be divided in transmission into fifty elemental parallel strips, or 2500 elemental areas. While such a division may be ade uate for the present in television, it is not a equate for the transmission of still pictures; and the requirements of television will undoubtedly call for far more detail to be preserved than is conveniently possible b the use of a scanning disk of the present orm' when the problems of transmission at higher frequencies are solved. It is quite apparent that the present scanning disk cannot be provided with sufficient apertures to ,divide a view into such a number oi? elemental areas as would compare favorably with the rotating film-cylinder system (which ordinarily is made to divide a five by seven picture into 100 bands to the inch, or into 350,000 elemental areas) without becoming inordinately large in diameter.

Thus the rotating film cylinder is not adapted to-transmit directly from an object or photograph, although this system attains a certain excellence'in the preservation of detail. And while the televison scanning disk, if utilized in the transmission of still would make possible such transmission directly from the object, or from a photograph thereof, the resent television scanning disk is entirely inadequate as regards the preservation of detail in such a s stem. Further, while the present television scannin disk may be ade uate in television for t e present state 0 the art, it will not be adequate when it becomes expedient to transmlt moving pictures without great loss of detail.

Accordingly, it is an object of my invention to provide a scanning device adapted to transmit pictures either from transparencies, photographs or physical objects, and to accomplish this by dividing the view into as great a number of elemental areas as may .be desired, or as may be transmittable, consigering other factors of the system availa e.

The invention will be most clearly understood from the following detailed descripthe a smaller scale, and showing the parts in.

another position; d lig. 3 is an end elevation of the rotating Fig. 4 is a vertical section taken on line H of Fig. 2;

Fig. 5, 5* and 5 are similar fragmentary vertical sections taken on line 55 of Fig. 2, showing successive operative positions of certain parts of the mechanism;

Fig. 6 is a horizontal fragmentary section taken on line 66 of Fig. 5;

Fig. 7 is a detail of the yoke portion of the shifter rod; and

Fig. 8 is a vertical section taken on line 8-8 of Fig. 4.

Referring to Fig. 1 ofthe drawings, the numeral 10 indicates a rotating disk or carrier for certain parts of thescanning mechanism, disk 10 being mounted on a shaft 11 journalled in suitable bearings driven by an electric motor 13.

Referring now to Figs. 1, 2, 3, 4 and 8, disk 10 is provided with a pair of guide strips 15 which carry slidably an aperture plate 16 having a li ht aperture 17. Plate 16 is adapted to sli e between the two end positions shown in full and dotted lines in Fig. 4. A light passingopening or slot 18 is provided in disk 10 in register with the path traversed by aperture 1'7 as plate 16 is carried between its end positions. There is thus provided a light aperture carried by arotatable disk at a continuously variable distance from its axis of rotation. Means now to be described are provided for moving the aperture plate in its guides as the disk rotates, for t e purpose of giving the light aperture motion in two directions with respect to the view being scanned, whereby the entire area of the view is traversed by the light aperture in a series of parallel bands. The narrowness of these bands, and the consequent fineness of preserved detail, will depend, of course, upon the characteris-- tics of the aperture plate moving means.

reference is had to the.

12 and is journaled in a bearing 23 provided upon a bracket 23 secured to disk 10. Fastened on the end of screw 21'adjacent bearing 23 is a spur gear 24, meshing with spur gear 25 on shaft 26, which shaft is journalled in a bearing 27 also provided on disk-bracket 23. The reduced portion 21 of lead screw 21 provides an annular shoulder 29 thereon, and encircling reduced portion 21 between this shoulder and the adjacent end of bearing 23 there is preferably provided an expansion sprin 30 to take up wear and looseness and insure preciselead screw movement.

It may now be seen'that rotation of shaft 26 drives screw 21 and causes aperture plate 16 to be carried toward or away from the axis of the disk, the direction of movement depending, of course, upon the direction of rotation of shaft 26. Means are now provided for driving shaft 26 in both directions, so that operation ma be carried on with plate 16 moving in either direction in its guides across disk 10.

On the end of shaft 26 adjacent gear 25 is a wheel 29, com rising a head 31 on the end of shaft 26 ac jacent gear 25, which is provided with a plurality of outwardly extending teeth or prongs 31, here shown as five in number. These teeth are adapted to be contacted by one or the other of a pair of fingers 32 and 33 respectively, formed on a bar 34 that is pivotally mounted on a sta tionary sup ort, and is adapted to occupy either the ull or dotted line positions of Fig. 6. As shown in Figs. 2, 5 and 6, bar

'34 is carried between the upper and lower walls 36 and 37 of a frame bracket 38, upon a pivot pin 40 fixed therein, said frame bracket being stationarilymounted upon a base member indicated at 41.

When bar34 occu ies the position shown in Fig. 2, (the full hne position of Fig. 6),

finger 32 is outwardly extended toward wheel 29 in operative relation thereto, and is contacted by a tooth 31 of wheel 29 as the wheel is carried past on each revolution of disk 10. The wheel is thereb. given a rotation on its own axis throug a predetermined angle, which in the present instance is a fifth of a revolution or 7 2 'de rees. This operation will be understood 0 early from reference to Figs. 5, 5 and 5, which show successive positions of wheel 29 as it is moved by finger 32, disk 10 being understood to rotate in a left-handed direction as viewed in Fig. 3, and consequently carrying wheel 29 upwardly in Figs. 5, 5" and 5", as indicated by vertical arrows. In the upper figure, tooth. 1 of wheel 29 is just comm into contact with the operative finger 32 0 bar 34. As the wheel continues in ward movement to the position of Fi 5*, and then continues on 'up to the final illustrated position of Fig. 5", finger 32 gives to its upwheel 29 a left handed rotation. The length of teeth 31 is so designed that the wheel, which is here shown as having five teeth, will be turned through just one-fifth of a revolution or 72 degrees as it is carried by finger 32, and the next tooth, number 2,

is thereby left positioned to be contacted and moved by finger 32 on the succeeding revolution of disk 10.

'l/Vhen bar 34 is moved to the dotted line position of Fig. 6, finger 32 is swung back out of line with the wheel, and finger 33 occupies an operative position with respect thereto, as shown in Fig. 2. In this case the teeth contact and are moved by finger 33. It will be obvious that since finger 33 is horizontally located on the op osite side of the wheel axis from finger 32, t e wheel is in this case caused to be rotated in the reverse direction.

Wheel 29 bein fixed on the end of shaft 26, this described movement transmits motion through gears 25 and 24 to lead screw 21, which finally imparts sliding motion to the aperture plate to shift the light aperture a slight distance either toward or away from the axis of disk 10, as the case may be, on each revolution of the said disk.

Means have now been described for shifting the aperture plate in its guides a slight distance for each revolution of the disk, the direction of movement of the plate depend ing upon the position occu ied by her 34. Automatic means will now e described for shifting the position of bar 34 as the aperture late reaches certain predetermined end positions, so that when the aperture plate reaches its end position at either end of its stroke, its direction of motion across disk 10 will automatically be reversed.

For this purpose, bracket 20 is provided with a depending arm 20 to which is fastened the end of a shifter rod 11. Rod 41 has a sliding fit through a bore 42 provided in the lower inner portion of bracket 23, and projects therebeyond to terminate in a shifter member 43, hereinafter more articularly described, which is adapts I to shift bar 34: between its two operative positions.

Bracket 38 is provided with means for yieldingly retaining pivoted bar 34 in either of its two positions. (see Fig. 6). This means may comprise a cam pin fifl having a sliding fit in a bearin 51 provided in the rear closed portion 52 o? bracket 38 and disposed in line with the pivot pin mounting 40 of bar 34. Pin 50 has near its forward end a flange 53, and encircling the pin between this fiange and the adjacent end of hearing 51 is an expansion spring 54. On the forward end of in 50 is formed a cam nose 50, which, an er the" ressure exerted by spring 54, co-operatcs with a pointed cam 56 formed on bar 34 just opposite pivot pin tions.

40, to yieldin ly retain the bar in either the full or dotte line positionsof Fig. 6, as will be clearly apparent.

On the end of bar 34 adjacent disk 10 is a ball 60, which is adapted to be contacted by the shifter member 43 of the shifter rod 41 for the urpose of shifting the position of bar 34 w en aperture plate 16 reaches its end positions.

Yoke 43 of shifter rod 41 comprises a cross bar connecting a pair of cams 66 and 67 (see Figs. 2 and 7), which are adapted to contact ball 60 to shift bar 34 when a erture plate 16 reaches its end posior instance, in Fig. 2 shifter rod 41 and the aperture plate moving bracket 20 are moving outward from the disk axis, as shown by the arrows. When cam 66 is finally carried to the dotted line position by the shifter rod, it will contact-ball 60 during its rotation with disk 10, and will throw the ball and bar 34 past the midposition, when spring 54 will act with cam pin 50 to complete the movement ofthe parts to the position of Fig. 2". This will reverse the direction of rotation of'wheel 29, and cause aperture late 16, bracket 2C) and shifter rod 41 to e reversed in motion across disk 10, in the manner previousl explained. The parts are then positioned and moving as in Fig. 2 ,.and when cam 67 reaches ball 60in the phase of operation illustrated in that fi ure, bar 34 will be shifted back to the rst osition, and the parts will again be reverse in motion across disk 10.

The preferred specific embodiment now described may be arranged in an optical system so that its light aperture will be effective for scanning a view area at a oint in the rotation of its carrier disk at whlch the aperture plate is not in the operation of being shifted thereon. The device will then carry the aperture across the view area in a series of parallel bands, one band being traversed as the aperture is carried over the view area at the completion of one revolution of the carrier disk, the aperture being shifted the width of one band after leaving the view area and while the disk is making its next revolution, and then u on returning to the View area traversing t e next band, and so on, to cover the entire area.

The use of my device will now be understood by those versed in the art to which it pertains without the necessity for here further describing optical and electrical picture transmitting systems in which it may be included. v

From what has been said, it will be apparent that I have provided a scanning device adapted to transmit views scanned di rectly from transparencies, photogra hs, PhXSlCfll ob ects or images thereof, at Willi feature of my invention is that the light aperture shifting mechanism may conveniently be so desi ed that an extremely narrow band of the image is covered during each rotation of the disk, thereby insuring preservation of the greatest amount of structure and detail of the original view.

As another feature of my invention, attention is called to the fact that the device 0 erates with the aperture plate moving in either direction across the view, and that automatic means are provided for shifting its direction of motion as it reaches its end positions, so that as long as the disk rotates the aperture will be oscillated across the view.

\Vhile I have herein illustrated and described certain specific means for carrying out an embodiment of my invention, it will be obvious that numerous changes and modifications may be made without departing from the spirit and scope of my invention; and it is therefore to be understood that all such modifications are contemplated within the scope of my invention as expressed in the following claims.

I claim: I

1. In a device of the character described, the combination of a carrier adapted to be rotated on an axis, an aperture plate carried about said axis by said carrier, said aperture piate having a light aperture, and means for moving the aperture plate on the carrier-as the carrier is rotated, in a direction substantially at right angles to its direction of motion due to rotation about the said carrier axis.

2. In a device of the character described, the combination of a carrier adapted to be rotated on an axis, an aperture plate slidably mounted on said carr1er so as to be movable with respect to the axis of rotation of the said carrier, said aperture plate having a light aperture, and means for moving the aperture plate on the carrier as the carrier is I rotated. k

3. In a device of the character described, the combination of a carrier adapted to be rotated on an axis, an aperture plate slidably mounted on said carrier so as to be movable with respect to the axis of rotation of the said carrier, said aperture plate having a light aperture, and intermittently acting means for moving the aperture plate on the carrier as the carrier is rotated.

4. In a device of the character described, the combination of a carrier adapted to be rotated on an axis, an aperture plate carried about said axis by said carrier, said aperture plate having a light aperture, and intermittently acting means for moving the aperture plate at the end of each revolution about the said carrier axis, in a direction substantially at right angles to its direction of moaxis.

5. In a device of the character described,

the combination of a carrier adapted to be during each revolution of the carrier, and

means operative when the aperture plate reaches the said limitin end positions on the carrier for automatica ly reversing its direction of motion thereupon.

6. In a device of the character described, the combination of a carrier adapted to be rotated about an axis, an aperture plate mounted on said carrier to be movable between predetermined limiting end positions in a direction at right angles to the direction of its movement due to rotation of the carrier, said aperture plate having a light aperture, intermittent means for moving the aperture plate on the carrier a short distance during each revolution of the carrier, and means operative when the aperture plate reaches the said limitin end positions on the carrier for automatically shifting the aperture plate moving means to reverse the direction of motion of the aperture plate upon the carrier.

'3'. In a device of the character described, the combination of a carrier adapted to be rotated about an axis, an aperture plate mounted on said carrier to be movable between predetermined limiting end ositions in a direction at right angles to the irection of its movement due to rotation of the carrier, said a erture plate having a light aperture, an means intermittently actuated by contact with a stationary member for moving the aperture plate on the carrier a short distance during each revolution of the carrier.

8. In a device of the character described, the combination oi a carrier mounted to rotate on its axis, an aperture plate mounted on said carrier to be movable toward and away from said carrier axis, said aperture ]plate having a light aperture, a lead screw aving screw threaded connection with the aperture plate, and mounted in hearings on t e carrier disk, and means for rotating the lead screw on its axis through a predetermined angle during each. revolution of the carrier dish.

9. In a device of the character described, the combination of a carrier mounted to rotate on its axis, an aperture plate mounted on said carrier to be movable toward and away from said carrier axis, said a erture plate having a light aperture, a lea screw aving screw threaded connection with the aperture plate, and turnably mounted on aving screw threaded connection with the v a t e carrier, lead screw driving means mounted on said carrier, and stationarily mounted means for contacting with said driving means during each revolution of the carrier to effect rotation of the lead screw on its axis through a predetern'iiued angle, whereby the aperture plate is shifted on the carrier during each revolution thereof.

H. In a device of the character described, the combination of a carrier mounted to rotate on its axis, an aperture plate mounted on said carrier to be movable between predetermined end positions toward and away from. said carrier axis, said aperture plate having a light aperture, a lead screw having screw threaded connection with the aperture plate, and turnably mounted on the carrier, lead screw driving means mounted on said carrier, stationarily mounted means shiftahle between two operative positions for contacting with said driving means during each revolution of the carrier disk to effect rotation of the lead screw on its axis through a predetermined angle in one direction when shifted to one position, and in the other direction when shifted to the other position, whereby the aperture plate is shifted on the carrier during each revolution thereof, in a direction determined by the position occupied bysaid stationaril mounted shiftable means, and means for shifting said stationarily mounted means when the aper-- ture plate reaches its. predetermined end positions.

12. In a device of the character described, the combination of a carrier mounted to rotate on its axis, an aperture plate mounted on said carrier to be movable between predetermined end positions toward and away from said carrier axis, said aperture plate having a light aperture, a lead screw having screw threaded connection with the aperture plate, and turnably mounted on the carrier,

lperture plate, and turnably mqunted onlead screw driving means mounted on said carrier, stationarily mounted means shift able between two operative positions for contacting with said driving means during each revolution of the carrier to effect rotation of the lead screw on its axis through a predetermined angle in one direction when shifted to one osition, and in the other direction when s ifted to the other osition,

whereby the aperture' plate is shifted on the carrier during each revolution thereof, in a direction determined by the position occupied by said stationarily mounted shiftable means, and automatic means for shift ing the position of said stationarily mounted means when the aperture plate reaches its predetermined end positions.

' 13. In a device of the character described, the combination of a carrier mounted to ro- 10 tate on its axis, an aperture plate mounted on said carrier to be movable between predetermined end positions, toward and away from said carrier axis, said aperture plate having a light aperture, a lead screw having screw threaded connection with the aperture plate, and turnably mounted in bearings on the carrier, lead screw driving means mounted on said carrier disk, stationarily mounted means shiftable between two 0 erative positions for contacting with said riving means during each revolution of the carrier to eilect rotation of the lead screw on its axis through a predetermined angle in one direction when shifted to one position, and in the other direction when shifted to the other position, whereby the aperture plate is shifted on the carrier during each revolution thereof, in a direction determined by the position occupied by said stationarily Q mounted shiitable means, and means carried by the moving aperture plate for contacting with said stationarily mounted means to cause shifting thereof when said aperture plate reaches its end positions.

In witness that I claim the foregoing I have hereunto subscribed my name this 1st day of February, 1929.

ELMER A. TAMBERT. 

